As I've noted previously, the "card market" can be insane ... pretty much "what the market will bear", tempered by card rarity. As an example, I was bidding just now on two cards, these were available for sale at my "low" reference site for $6.00 and $5.00 respectively, at my "medium" reference site for $6.99 and $5.99, and at my "high" reference site for $5.99 and $19.99 ... these ended up selling (before shipping) for $1.27 and $2.62 ... as they were cards for a set from which Daughter #1 was only missing a few cards, I was willing to go out side of my ".14" target price zone, but I was unwilling to start pushing half or higher.
Needless to say, if these foreign card vendors are re-selling their wins in Pounds or Euros at the rates that some of these sites get (note the $19.99 above), they have a lot of "ceiling" for bidding up these prices. I just find it depressing when they sweep in at the last minute ... it "takes all the fun out of it" for me.
Boo-hoo-hoo :-(